I’m giving you my opinion on what “we” should do. It is entirely appropriate - indeed almost unavoidable - to use the first person plural in that instance. I made it clear that I’m only giving my opinion. I’m not saying “this is what we (including you) believe”. I am saying “this is what we (including you) ought to believe.” So I am speaking only for myself.
Incorrect. You made an assertion about what "we" know.
You (singular) may know (or think you know) what you asserted to be collective "knowledge". That's your problem. Refrain from projecting it onto others.